Silicon carbide (SiC) power devices have been investigated extensively in the past two decades, and there are many devices commercially available now. Owing to the intrinsic material advantages of SiC over silicon (Si), SiC power devices can operate at higher voltage, higher switching frequency, and higher temperature. This paper reviews the technology progress of SiC power devices and their emerging applications. The design challenges and future trends are summarized at the end of the paper.

https://ieeexplore.ieee.org/ielaam/41/8031005/7815312-aam.pdf

Review of Silicon Carbide Power Devices and Their Applications

This paper contributes to the steady-state analysis of the bidirectional dual active bridge (DAB) dc-dc converter by proposing a new model that produces equations for rms and average device currents, and rms and peak inductor/transformer currents. These equations are useful in predicting losses that occur in the devices and passive components and aid in the converter design. An analysis of zero-voltage switching (ZVS) boundaries for buck and boost modes while considering the effect of snubber capacitors on the DAB converter is also presented. The proposed model can be used to predict the converter efficiency at any desired operating point. The new model can serve as an important teaching-cum-research tool for DAB hardware design (devices and passive components selection), soft-switching-operating range estimation, and performance prediction at the design stage. The operation of the DAB dc-dc converter has been verified through extensive simulations. A DAB converter prototype was designed on the basis of the proposed model and was built for an aerospace energy storage application. Experimental results are presented to validate the new model for a 7 kW, 390/180 V, 20 kHz converter operation and the ZVS boundary operation.

High-Power Bidirectional DC–DC Converter for Aerospace Applications

Aiming for converters with high efficiency and high power density demands converter topologies with zero-voltage switching (ZVS) capabilities. This letter shows that in order to determine whether ZVS is provided at a given operating point, the stored charge within the mosfet s has to be considered and the condition $L I^2 \geq 2Q_\text{oss} V_\text{DC}$ has to be fulfilled. In the case of incomplete soft switching, nonzero losses occur which are analytically derived and experimentally verified in this letter. Furthermore, the issue of nonideal soft-switching behavior of Si superjunction mosfet s is addressed.

ZVS of Power MOSFETs Revisited

This study deals with the optimal control of hybrid energy storage systems for electric vehicle applications. These storage systems can capitalize on the high specific energy of Lithium-Ion batteries and the high specific power of modern ultracapacitors. The new predictive algorithm uses a state-based approach inspired by power systems optimization, organized as a probability-weighted Markov process to predict future load demands. Decisions on power sharing are made in real time, based on the predictions and probabilities of state trajectories along with associated system losses. Detailed simulations comparing various power sharing algorithms are presented, along with converter-level simulations presenting the response characteristics of power sharing scenarios. The full hybrid storage system along with the mechanical drivetrain is implemented and validated experimentally on a 500 W, 50 V system with a programmable drive cycle having a strong regenerative component. It is experimentally shown that the hybrid energy storage system runs more efficiently and captures the excess regenerative energy that is otherwise dissipated in the mechanical brakes due to the battery's limited charge current capability.

Predictive Algorithm for Optimizing Power Flow in Hybrid Ultracapacitor/Battery Storage Systems for Light Electric Vehicles

A switched-capacitor bidirectional dc–dc converter with a high step-up/step-down voltage gain is proposed for electric vehicles with a hybrid energy source system. The converter presented has the advantages of being a simple circuit, a reduced number of components, a wide voltage-gain range, a low voltage stress, and a common ground. In addition, the synchronous rectifiers allow zero voltage switching turn-on and turn-off without requiring any extra hardware, and the efficiency of the converter is improved. A 300 W prototype has been developed, which validates the wide voltage-gain range of this converter using a variable low-voltage side (40–100 V) and to give a constant high-voltage side (300 V). The maximum efficiency of the converter is 94.45% in step-down mode and 94.39% in step-up mode. The experimental results also validate the feasibility and the effectiveness of the proposed topology.

/pdf/a-switched-capacitor-bidirectional-dc-dc-converter-with-wide-4fru054evl.pdf

A Switched-Capacitor Bidirectional DC–DC Converter With Wide Voltage Gain Range for Electric Vehicles With Hybrid Energy Sources

A novel zero current soft-switching (ZCS) pulse-width modulation (PWM) bidirectional dc–dc converter (BDC) with non-inverting polarity multi-mode voltage regulations is presented. In the proposed BDC, all the power devices commutate in ZCS with the aid of single-auxiliary switch-based edge-resonant cells; accordingly the switching power losses can be minimised. The effectiveness of the proposed BDC and its steady-state characteristics are verified in experiments with a 500 W–50 kHz prototype.

https://ietresearch.onlinelibrary.wiley.com/doi/pdf/10.1049/el.2015.1174

Inductor-link open H-bridge topology-based ZCS-PWM bidirectional dc–dc converter with edge-resonant switching cells

高周波誘導加熱用ブリッジレスbhb zvs-pwm周波数変換器

Research on All Operation Modes of Chopper Circuit Topology Incorporating Series Connection of Buck and Boost Choppers

A novel high-frequency resonant inverter operating under a complete zero current soft transition mode is originally proposed in this letter, which can be continuously controlled by regulating phase difference angle between two resonant currents under the fixed switching frequency. Its operating principle and unique features are described herein by simulation analysis for high-frequency low resistivity induction heating of metal vessels. Furthermore, its output power regulation vs. phase-shifted angle characteristics are demonstrated under the condition of complete ZCS operation.

A New Proposal of An Instantaneous Resonant Complex Current Vector Controlled High-Frequency Soft-Switching Inverter Topology for Induction Heating

This paper presents 2 active edge resonant cell interleaved boost DC-DC converter. It uses two feedback loops including similar to current mode control with one slow outer loop and the other for faster inner PWM control loop. To improve the transient response of the 2-cell assisted ZCS boost converter system, a coupled inductor of energy storage inductors is used on the basis of interleave architecture. This integrated magnetic design structure reduces size as well as weight and improves the converter performance due to both steady-state and transient. The effectiveness of the proposed converter and control scheme is demonstrated through PSIM simulations.

Tomokazu Mishima

Papers

Inductor-link open H-bridge topology-based ZCS-PWM bidirectional dc–dc converter with edge-resonant switching cells

高周波誘導加熱用ブリッジレスbhb zvs-pwm周波数変換器

Research on All Operation Modes of Chopper Circuit Topology Incorporating Series Connection of Buck and Boost Choppers

A New Proposal of An Instantaneous Resonant Complex Current Vector Controlled High-Frequency Soft-Switching Inverter Topology for Induction Heating

Interleaved ZCS boost DC-DC converters with coupled inductor using active edge resonant switch blocks for PV interface